Advanced Web Statistics (AWStats) is a free powerful Web server logfile analyzer (Perl script) that shows you all your Web statistics including visits, unique visitors, pages, hits, rush hours, search engines, keywords used to find your site, robots, broken links, and more. It works with both IIS 5.0+ and Apache Web server log files as a CGI and/or from the command line. It also supports around 40 languages.
RadiusReport can analyse the logfiles produced by all the major Radius Servers including Livingston Radius V2.0+, V1.16, Merit Radius, Ascend Radius, Dale Reed's RadiusNT, Radiator Perl Radius Server, but excluding Microsoft Radius. It will allow you to produce many, varied, types of reports from one or multiple radius log files.
RadiusSplit is a Perl program designed to take, as input, one or more large RADIUS accounting "detail" log files, and split them out into individual files - one per user. The net result is that you will have a detail file per user, which can be passed to other RADIUS parsing logfile analysers (e.g. RadiusReport) so they run much faster (usually be a factor of several hundred), since they don't have to parse and discard the non-relevant data.